Rho-dependent inhibition of the induction of connective tissue growth factor (CTGF) by HMG CoA reductase inhibitors (statins)
作者:Michael Eberlein、Juliane Heusinger-Ribeiro、Margarete Goppelt-Struebe
DOI:10.1038/sj.bjp.0704173
日期:2001.8
It was supposed that inhibitors of 3‐hydroxy‐3‐methylglutaryl‐coenzyme A (HMG CoA) reductase (statins) might inhibit the expression of the fibrosis‐related factor CTGF (connective tissue growth factor) by interfering with the isoprenylation of Rho proteins.
The human renal fibroblast cell line TK173 was used as an in vitro model system to study the statin‐mediated modulation of the structure of the actin cytoskeleton and of the expression of CTGF mRNA.
Incubation of the cells with simvastatin or lovastatin time‐dependently and reversibly changed cell morphology and the actin cytoskeleton with maximal effects observed after about 18 h.
Within the same time period, statins reduced the basal expression of CTGF and interfered with CTGF induction by lysophosphatidic acid (LPA) or transforming growth factor beta. Simvastatin and lovastatin proved to be much more potent than pravastatin (IC50 1–3 μM compared to 500 μM).
The inhibition of CTGF expression was prevented when the cells were incubated with mevalonate or geranylgeranylpyrophosphate (GGPP) but not by farnesylpyrophosphate (FPP). Specific inhibition of geranylgeranyltransferase‐I by GTI‐286 inhibited LPA‐mediated CTGF expression whereas an inhibitor of farnesyltransferases FTI‐276 was ineffective.
Simvastatin reduced the binding of the small GTPase RhoA to cellular membranes. The effect was prevented by mevalonate and GGPP, but not FPP.
These data are in agreement with the hypothesis that interference of statins with the expression of CTGF mRNA is primarily due to interference with the isoprenylation of RhoA, in line with previous studies, which have shown that RhoA is an essential mediator of CTGF induction.
The direct interference of statins with the synthesis of CTGF, a protein functionally related to the development of fibrosis, may thus be a novel mechanism underlying the beneficial effects of statins observed in renal diseases.
British Journal of Pharmacology (2001) 133, 1172–1180; doi:10.1038/sj.bjp.0704173
假设羟甲基戊二酰辅酶 A(HMG-CoA)还原酶抑制剂(他汀类药物)可能通过干扰 Rho 蛋白的牻牛儿基牻牛儿基化作用来抑制与纤维化相关的因子 CTGF(结缔组织生长因子)的表达。
以人肾成纤维细胞系 TK173 作为体外模型系统,研究他汀类药物介导的肌动蛋白细胞骨架结构以及 CTGF mRNA 表达的调控作用。
将细胞分别与辛伐他汀或洛伐他汀共同孵育,细胞形态及肌动蛋白细胞骨架在时间依赖性和可逆性变化下,约 18 小时时观察到最大效应。
在同一时间段内,他汀类药物降低了 CTGF 的基础表达,并干扰了 CTGF 由溶血磷脂酸(LPA)或转化生长因子 β 所诱导的表达。辛伐他汀和洛伐他汀的作用远强于普伐他汀(IC₅₀ 1–3 μM 与 500 μM 相比)。
当细胞与甲羟戊酸或牻牛儿基牻牛儿基二磷酸(GGPP)共同孵育时,CTGF 表达的抑制作用被逆转,而法尼基二磷酸(FPP)则无效。使用 GTI-286 特异性抑制牻牛儿基牻牛儿基转移酶 I 抑制了 LPA 介导的 CTGF 表达,而法尼基转移酶抑制剂 FTI-276 无效。
辛伐他汀降低了小 GTP 酶 RhoA 在细胞膜的结合。该作用被甲羟戊酸和 GGPP 阻断,但 FPP 无效。
数据支持他汀类药物通过干扰 RhoA 的牻牛儿基牻牛儿基化作用影响 CTGF mRNA 表达的假设,这与先前研究表明 RhoA 是 CTGF 诱导的关键介质一致。
他汀类药物直接干扰 CTGF(与纤维化相关蛋白质)合成,可能是在肾脏疾病中观察到的他汀类药物有益作用的新机制。
*《英国药理学杂志》* (2001), **133**, 1172–1180; **DOI:** [10.1038/sj.bjp.0704173](https://doi.org/10.1038/sj.bjp.0704173)